<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8" />
  <meta name="viewport" content="width=device-width, initial-scale=1.0" />
  <meta http-equiv="X-UA-Compatible" content="ie=edge" />
  <title>Document</title>
  <style>
    #hideCanvas {
      position: absolute;
      z-index: 1;
      visibility: hidden;
      left: 0;
      top: 0;
      width: 100vw;
      height: 100vh;
    }

    #canvas {
      position: relative;
      z-index: 2;
      width: 100vw;
      height: 100vh;
    }

    .drawContainer {
      position: relative;
    }
  </style>
</head>

<body>
  <div class="drawContainer">
    <canvas id="canvas"></canvas>
    <canvas id="hideCanvas"></canvas>
  </div>
  <script src="./index.js"></script>
</body>

</html>